Arithmetic logical unit is a critical part of all microprocessor based equipment as it performs all the primary functions. This paper focuses the implementation of 32 bit ALU on FPGA for the Antenna Control Unit processor. Antenna control unit is a subsystem used in telecommunication to automatically track, monitor and control the RF signals. The authors' ALU is implemented by using modular approach i.e. control unit, logical unit, arithmetic unit and relational operations unit. Control Unit is a state machine that issues commands for all the operations.